Current minimum smoke rocket motor solid propellants produce fuel rich exhaust products that combust or afterburn with air beyond the nozzle exit of the rocket motor. Such afterburning does not contribute to rocket motor thrust, is undesirable, and in many cases is unacceptable because it increases the radiation emission signature of the missile.
There are many documented approaches for the use of chemical means to suppress afterburning, however they have not been proven to be acceptable for accomplishing the desired results in afterburning. Depending upon the nature of the chemicals used, various previous methods have included: (1) the incorporation of the chemical suppressant into the main rocket motor propellant itself, (2) coating resonance rods with the chemical suppressants and placing them inside the rocket motor structure and (3) using ablative nozzle rings or sections in the rocket motor for providing suppressant for the rocket motor.
Many solid propellants that are used in these minimum smoke type solid propellants are chemically or otherwise incompatible with the suppressant so that direct incorporation into the minimum smoke solid propellant is not possible. In these prior devices, the ablative technique is ineffective and requires large amounts of suppressant that results in smoke signature. Therefore, it can be seen that a device or technique that is effective in eliminating or effectively controlling afterburning in a rocket motor is badly needed.
Accordingly, it is an object of this invention to provide a new device and technique for introducing a fluid chemical flash suppressant into the exhaust gases of a rocket motor so as to cause a chemical reaction between the chemical fluid and the exhaust gases to reduce the flash signature.
Another object of this invention is to provide an arrangement which utilizes an igniter for igniting both a solid propellant and a dispenser grain for dispensing a fluid chemical flash suppressant.
Still another object of this invention is to provide a device which utilizes a technique of injecting fluid chemical material into rocket motor exhaust gases by means of a dispenser grain which produces gas and causes the fluid chemical material to be ejected and into the exhaust gases as the dispenser grain burns.
A still further object of this invention is to provide an arrangement which can utilize a fluid chemical flash suppressant that can be dispensed over a temperature range of about -60.degree. F. to about 180.degree. F.
Other objects and advantages of this invention will be obvious to those skilled in this art.